This invention relates to an electric motor housing. More particularly, the invention relates to a method and apparatus for encapsulating an unsealed DC motor to adapt such motor to operations submerged in water as for an electric trolling motor of a boat.
In recent years, fishermen have come to rely on an electric outboard motor, generally known as a "trolling motor", for boating noiselessly through water without alarming wary fish. Power for such motors is commonly supplied by a direct current voltage source, such as a wet cell DC battery, carried aboard the boat.
Electric trolling motors of this type characteristically fall into one of two categories. The hand operated type of trolling motor includes an elongate shaft having a water tight direct current motor equipped with a propeller on the work shaft. Electrical leads from the motor extend up through the elongate shaft to a control lever having a handle for rotating the direction of the motor and having a switch and/or speed control for operating the motor. Electrical leads from the control handle are connected to the power source. The second type of trolling motor is commonly referred to as a remote control or foot operated trolling motor and enables the fisherman to have free use of his hands since directional control of the motor as well as on-off operation and/or speed control is accomplished by the foot acting on a pedal lever which has the necessary switch and any speed control associated therewith.
Heretofore, both of the foregoing types of electric trolling motors have employed a sealed DC motor which is necessary to prevent water from seeping into the motor when it is submerged in water during normal operation. The necessity of using sealed motors represents a significant portion of the total expense of an electric trolling motor. It also represents a significant and time consuming maintenance problem, which, if repair or replacement is dictated, is likewise expensive.
Consequently, there is a need in the field of electric trolling motors for a method of effectively employing an unsealed DC motor in water submerged operations. The primary goal of this invention is to fulfill this need.
More specifically, an object of this invention is to provide the method and apparatus for encapsulating an unsealed DC electric motor in a water tight housing to permit use as the motor and propeller unit of an electric trolling motor.
Another object of the invention is to provide an encapsulated unsealed DC motor for an electric trolling motor having a strong and water impervious housing to prevent water damage to the unsealed motor.
An additional object of the invention is to provide an encapsulated unsealed electric motor for an electric trolling motor wherein the motor is rigidly held within the housing in order to prevent vibrational damage and thereby insure a long and useful life of the unit.
Another object of the invention is to provide an encapsulation housing for an unsealed DC motor of the character described wherein the motor work shaft is bearingly received with respect to the housing in order to permit rotation of the work shaft and is also effectively sealed thereagainst in order to prevent water seepage around the work shaft.
Other and further objects of the invention, together with the features of novelty appurtenant thereto, will appear in the course of the following description of the drawing.